Semiconductor device having capacitor capable of reducing additional processes and its manufacture method
View Patent ↗A first capacitor recess and a wiring trench are formed through an interlayer insulating film. A lower electrode fills the first capacitor recess, and a first wiring fills the wiring trench. An etching stopper film and a via layer insulating film are disposed over the interlayer insulating film. A first via hole extends through the via layer insulating film and etching stopper film and reaches the first wiring, and a first plug fills the first via hole. A second capacitor recess is formed through the via layer insulating film, the second capacitor recess at least partially overlapping the lower electrode, as viewed in plan. The upper electrode covers the bottom and side surfaces of the second capacitor recess. A capacitor is constituted of the upper electrode, etching stopper film and lower electrode. A second wring connected to the first plug is formed over the via layer insulating film.
1. A semiconductor device comprising:
a first interlayer insulating film formed over a semiconductor substrate;
a first capacitor recess and a wiring trench formed through the first interlayer insulating film;
a lower electrode embedded in the first capacitor recess;
a first wiring embedded in the wiring trench;
a first etching stopper film disposed over the first interlayer insulating film;
a via layer insulating film disposed over the first etching stopper film and made of insulating material having an etching resistance different from an etching resistance of the first etching stopper film;
a first via hole formed through the via layer insulating film and the first etching stopper film and reaching an upper surface of the first wiring;
a first plug made of conductive material embedded in the first via hole;
a second capacitor recess formed through the via layer insulating film and reaching the first etching stopper film, the second capacitor recess at least partially overlapping the lower electrode as viewed in plan;
an upper electrode including a first barrier metal film and a first conductive film, the first barrier metal film covering a bottom surface and a side surface of the second capacitor recess and a partial upper surface of the via layer insulating film continuous with the second capacitor recess, the first conductive film being deposited on the first barrier metal film and being continuous from a portion filing the second capacitor recess to a portion deposited on the barrier metal film covering the partial upper surface of the via layer insulating film, the upper electrode and the lower electrode constituting a capacitor comprising the first etching stopper film as a capacitor dielectric film; and
a second wiring formed over the via layer insulating film and connected to the first plug, the second wiring including a second barrier metal film and a second conductive film, the second barrier metal film being deposited on the first plug and made of a same material as the first barrier metal film, and the second conductive film being deposited on the second barrier metal film and made of a same material as the first conductive film,
wherein an upper surface of the upper electrode has a recess reflecting a shape of the bottom surface and the side surface of the second capacitor recess.
2. The semiconductor device according to claim 1 , wherein the second capacitor recess is located within the lower electrode, as viewed in plan.
3. The semiconductor device according to claim 1 , wherein an area of the second capacitor recess is larger than an area of the first via hole, as viewed in plan.
4. The semiconductor device according to claim 1 , further comprising a pad formed over the via layer insulating film, wherein the pad has a same lamination structure as a lamination structure of the upper electrode.
5. The semiconductor device according to claim 1 , further comprising a cover film formed over the via layer insulating film and covering the upper electrode.
6. The semiconductor device according to claim 1 , further comprising:
a lead wiring trench formed in the first interlayer insulating film and being continuous with the first capacitor recess; and
a lead wiring embedded in the lead wiring trench and being continuous with the lower electrode.
7. The semiconductor device according to claim 1 , wherein the first capacitor recess and the wiring trench reach partway in a depth direction of the first interlayer insulating film, the semiconductor device further comprises a third via hole extending from a bottom of the wiring trench to a bottom of the first interlayer insulating film, and a plug integrated with the first wiring is embedded in the third via hole.
8. The semiconductor device according to claim 1 , wherein the second barrier metal film is deposited on an upper surface of the via layer insulating film in an area continuous with the first via hole, and the second barrier metal film is not in contact with the first etching stopper film.
9. The semiconductor device according to claim 1 , wherein a shape of the second capacitor recess is a rectangle, as viewed in plan.
10. The semiconductor device according to claim 1 , wherein the first etching stopper film is a silicon carbide.
11. The semiconductor device according to claim 1 , wherein the first etching stopper film comprises a silicon carbide.
12. The semiconductor device according to claim 1 , wherein the first interlayer insulating film comprises a silicon oxycarbide.
13. The semiconductor device according to claim 12 , wherein the via layer insulating film comprises a silicon oxycarbide.
14. A semiconductor device comprising:
a first interlayer insulating film formed over a semiconductor substrate;
a first capacitor recess and a wiring trench formed through the first interlayer insulating film;
a lower electrode embedded in the first capacitor recess;
a first wiring embedded in the wiring trench;
a first etching stopper film disposed over the first interlayer insulating film;
a via layer insulating film disposed over the first etching stopper film and made of insulating material having an etching resistance different from an etching resistance of the first etching stopper film;
a first via hole formed through the via layer insulating film and the first etching stopper film and reaching an upper surface of the first wiring;
a first plug made of conductive material embedded in the first via hole;
a second capacitor recess formed through the via layer insulating film and reaching the first etching stopper film, the second capacitor recess at least partially overlapping the lower electrode as viewed in plan;
an upper electrode including a first barrier metal film and a first conductive film, the first barrier metal film covering a bottom surface and a side surface of the second capacitor recess and a partial upper surface of the via layer insulating film continuous with the second capacitor recess, the first conductive film being deposited on the first barrier metal film and being continuous from a portion filing the second capacitor recess to a portion deposited on the barrier metal film covering the partial upper surface of the via layer insulating film, the upper electrode and the lower electrode constituting a capacitor comprising the first etching stopper film as a capacitor dielectric film;
a second wiring formed over the via layer insulating film and connected to the first plug, the second wiring including a second barrier metal film and a second conductive film, the second barrier metal film being deposited on the first plug and made of a same material as the first barrier metal film, and the second conductive film being deposited on the second barrier metal film and made of a same material as the first conductive film;
a pad formed over the via layer insulating film, the pad having a same lamination structure as a lamination structure of the upper electrode;
a cover film formed over the via layer insulating film, the cover film covering the upper electrode, the second wiring and the pad; and
an opening formed through the cover film, a part of the pad being exposed at a bottom of the opening.
15. A semiconductor device comprising:
a first interlayer insulating film formed over a semiconductor substrate;
a first capacitor recess and a wiring trench formed through the first interlayer insulating film;
a lower electrode embedded in the first capacitor recess;
a first wiring embedded in the wiring trench;
a first etching stopper film disposed over the first interlayer insulating film;
a via layer insulating film disposed over the first etching stopper film and made of insulating material having an etching resistance different from an etching resistance of the first etching stopper film;
a first via hole formed through the via layer insulating film and the first etching stopper film and reaching an upper surface of the first wiring;
a first plug made of conductive material embedded in the first via hole;
a second capacitor recess formed through the via layer insulating film and reaching the first etching stopper film, the second capacitor recess at least partially overlapping the lower electrode as viewed in plan;
an upper electrode including a first barrier metal film and a first conductive film, the first barrier metal film covering a bottom surface and a side surface of the second capacitor recess and a partial upper surface of the via layer insulating film continuous with the second capacitor recess, the first conductive film being deposited on the first barrier metal film and being continuous from a portion filing the second capacitor recess to a portion deposited on the barrier metal film covering the partial upper surface of the via layer insulating film, the upper electrode and the lower electrode constituting a capacitor comprising the first etching stopper film as a capacitor dielectric film;
a second wiring formed over the via layer insulating film and connected to the first plug, the second wiring including a second barrier metal film and a second conductive film, the second barrier metal film being deposited on the first plug and made of a same material as the first barrier metal film, and the second conductive film being deposited on the second barrier metal film and made of a same material as the first conductive film; and
a cover film covering upper surfaces and side surfaces of the upper electrode and the second wiring.